Verizon message+ uses more time in background

[Zo6]

Ive just been with Verizon for a week or so, but noticed that their message+ always uses way more time in the background than on screen time. Is there a setting to stop that, or just have to live with it? I use it at work for calls and text messages on wifi, because their signal doesn't come in the building. I have an iPhone 6s

 

[jpiszcz]

iOS 9.3 beta 3 supports native wifi calling/texting for Verizon